diff --git a/makefile b/makefile
index 277a714..7082311 100644
--- a/makefile
+++ b/makefile
@@ -64,6 +64,10 @@
   CFLAGS += -DDISABLE_FASTBOOT_CMDS=1
 endif
 
+ifeq ($(APPEND_CMDLINE),1)
+  CFLAGS += -D_APPEND_CMDLINE=1
+endif
+
 # setup toolchain prefix
 TOOLCHAIN_PREFIX ?= arm-eabi-
 CFLAGS += -fstack-protector-all